Field of the Invention
This invention relates to a murine hybridoma line that secretes a hamster monoclonal antibody that binds to the mouse CD28 receptor. The antibody has enhanced signal transduction properties compared to previously available reagents. The antibody permits ex vivo expansion of a population of T cells in the absence of exogenous growth factors, such as lymphokines, and accessory cells. The invention further pertains to methods of using the antibody and kits for providing the antibody.